Scenario
You have multiple email domains set up within your Tenant:
admin@crosswaredemo.com
admin@paperface.com
Your signature configuration is selected for one of the above.
Or your user account is "admin@crosswaredemo.com" but your email address is "admin@paperface.com"
Messages sent out with this configuration may have erratic results when appending a signature.
Solution
Creating an M365 Group
1. Log into your M365 Exchange Admin Center > Click the Recipients drop-down > Select Groups > Click Add a group to create the group (preferably a Distribution list group)
2. Add Members to the specific group.
Creating a Google Group
1. Log into your Google Admin Console > Go to the Directory drop-down option > Select Groups > Click Create group to add a new group
2. Click Add members to add members to add the relevant users
Assign the signature to the group created.
1. Log into your Crossware portal using your M365 global admin/portal admin account or your Google Workspace admin/portal admin account > Select the signature that needs assigning by clicking the Edit signature button.
2. Assign the recently created group by clicking the drop-down option under the Who is this signature for? > Select the Group option and search for the group using the search tool and click Add Group once you see the group. When the signature has been assigned, click SAVE & CLOSE to save any change(s) made.